Corn has been an important nutritional resource for thousands of years because of its high protein and carbohydrate content. Corn can be traced back to Mexican or central American cultures as early as 3400 B.C., and has become a staple among Native American civilizations throughout the Western Hemisphere. Today, corn has less starch and is sweeter. The sweetness accounts for its popularity among Americans. Its oil has good sensory qualities for use in salad preparation and cooking. [1]

Varieties, Selection and StorageThere are more than two hundred varieties of corn. All are good sources of vitamin C, but only yellow kernels contain small amounts of vitamin A in the form of beta carotene. Make sure the husks are green, tight and fresh looking. Pull the husk open to make sure that the ear contains tightly packed rows of plump kernels. The kernels should be smaller at the tip of each ear. Large kernels at the tip is a sign of overmaturity. If you pinch a kernel, milky juice should spurt out. Corn should be stored in a cool area. Warmth causes the sugar content of corn to be converted into starch. This process will cause the ears to become less sweet. If the corn is not cooked shortly after it is purchased, then it should be stored in refrigerator. Refrigeration helps the corn retain its sugar and vitamin C content. If you buy unhusked corn, keep it in its husk until you are ready to cook it. This will help the corn retain its moisture content. To fully enjoy the great taste of sweet corn, cook it as soon as possible._____________________________________________________________________________________________Nutrition Facts of corn

Corn has a good nutrition facts. The serving size of 1 medium ear is 90 g. It contains 130 calories, 2 g of total fat, 0 mg of cholesterol, 25 mg of sodium, 29 g of total carbohydrate, 4 g of dietary fiber, 9 g of sugars and 5 g of protein. Corn is also a source of anti-oxidants, iron, vitamins A and C._____________________________________________________________________________________________Potential Health Benefits of Corn

Corn also contains important chemicals called lectins. This unique group of proteins and glycoproteins attribute various health benefits of corns. Several lectins may possess anticancer properties in vitro, in vivo, and in human case studies; they may be used as anti-cancer agents, by binding to cancer cell membranes or receptors, causing cytotoxicity, apoptosis of the cancer cells, and consequently inhibition of tumor growth. [9]

In addition to the anti-cancer properties, consumption of corn (and other grains) is also associated with reduced risk of certain chronic diseases. The health benefits of corn are attributed in part to their unique phytochemical composition. [4]The major portion of phenolics in grains existed in the bound form (85% in corn, 75% in oats and wheat, and 62% in rice). In a study, ferulic acid was the major phenolic compound in grains tested, with free, soluble-conjugated, and bound ferulic acids present in the ratio 0.1:1:100. Corn had the highest total antioxidant activity (181.42 micromol of vitamin C equiv/g of grain), followed by wheat (76.70 micromol), oats (74.67 micromol), and rice (55.77 micromol). Bound phytochemicals were the major contributors to the total antioxidant activity: 90% in wheat, 87% in corn, 71% in rice, and 58% in oats. Bound phytochemicals could survive stomach and intestinal digestion to reach the colon. This may partly explain the mechanism of grain consumption in the prevention of colon cancer, other digestive cancers, breast cancer, and prostate cancer. [4]

Processed sweet corn provide more benefits than raw sweet cornVitamin C in apples has been found to contribute <0.4% of total antioxidant activity, indicating most of the activity comes from other phytochemicals. This suggests that processed fruits and vegetables may retain their antioxidant activity despite the loss of vitamin C. It was found that thermal processing at 115 degrees C for 25 min significantly elevated the total antioxidant activity of sweet corn by 44% and increased phytochemical content such as ferulic acid by 550% and total phenolics by 54%, although there was a loss of 25% vitamin C. Consequently, processed sweet corn has increased antioxidant activity equivalent to 210 mg of vitamin C/100 g of corn compared to the remaining 3.2 mg of vitamin C in the sample that contributed only 1.5% of its total antioxidant activity. [5]______________________________________________________________________________________________CORN OIL NUTRITION FACTS

Corn Oil PreparationBy removing free fatty acids and phospholipids from the crude corn oil, the refined corn oil has excellent frying quality and resistance to smoking or discoloration. Because of its pleasant taste, corn oil are often incorporated in margarines, cooking or salad oil.

Prior to the civil war, the main sources for starch had been wheat and potatoes. Corn refining began with the development of the process for corn starch hydrolysis. By 1857, the corn-starch industry reached significant proportions in the U.S. At that time, corn starch industry has only one product-starch. Today, products derived from corn starch include corn syrup, anhydrous sugar, maltodextrin, dextrose, glucose and starch. [8]

Nutritional facts and health benefits of corn oilRefined corn oil is composed of 99% triacylglycerols with polyunsaturated fatty acid (PUFA) 59%, monounsaturated fatty acid 24%, and saturated fatty acid (SFA) 13%. The polyunsaturated fatty acid is linoleic acid (C18: 2n-6) primarily, with a small amount of linolenic acid (C18: 3n-3) giving a n-6/n-3 ratio of 83. Linoleic acid is essential for skin and cell membrane integrity and icosanoids production. Icosanoids are necessary for reproductive, cardiovascular, renal, and gastrointestinal functions and resistance to disease. Corn oil is also a good source of of ubiquinone, alpha- and gamma-tocopherols (vitamin E). Because the consumption of corn oil can replace saturated fatty acids with polyunsaturated fatty acids and corn oil contains a large amount of polyunsaturated fatty acids, corn oil has benefits of cholesterol-lowering effects, in general. [1]

In a study, rats was supplmented with a low-fat diet (2.2% lard plus 2.2% corn oil), a corn oil diet (17%), a salmon oil diet (12.5%) plus 4.5% corn oil, or a lard diet (15%) plus 2% corn oil for eight weeks. All these diets contained 1% cholesterol. It was found that the salmon oil-diet lowered the blood cholesterol (-50%) and triglyceride (-56%) while the corn oil lowered the triglycerides by 40%. [2]

It was also found that phytosterols comprising less than 1% of commercial corn oil could substantially reduce cholesterol absorption and this might account for part of the cholesterol-lowering activity of corn oil from a study of healthy subjects with a mean serum cholesterol level of 5.1 mmol/L. The cholesterol absorption was 38% higher after consumption of the sterol-free corn oil than after consumption of commercial corn oil with an identical fatty acid content in a study of 10 healthy subjects. And, when corn oil phytosterols were added back to sterol-free corn oil at a concentration of 150 mg/test meal, cholesterol absorption was reduced by 12% after inclusion of 300 mg phytosterols. [3]

Corn oil side effectsAccording to a study from the University of Hawaii, fast-food chains are more likely than smaller restaurants to cook their French fries in corn oil, which is higher in cholesterol-raising saturated fats than other vegetable oils. An article from Bloomberg reports that the fry oil used now by the chains includes corn oil that is higher in saturated fats, that also raises cholesterol. [10]

Animal studies have shown that supply of polyunsaturated fatty acid is one of the requirements for cancer growth. Long-term dietary corn oil promotes azoxymethane-induced colon cancer development partly by inhibiting the tumor suppressor gene p53-mediated mitochondria-dependent apoptosis in a study of male Sprague-Dawley rats. [6] However, the amount of polyunsaturated fatty acid required for cancer growth is considered to be larger than that needed of the host. Thus, excessive intake of corn oil is not recommended. [1] In addition, a significant positive relation was found between mortality rate and the consumption of dietary corn and wheat flour was found in a study of esophageal cancer cases in Shanxi Province, China. [7]______________________________________________________________________________________________high fructose corn syrup

The replacement of sucrose with high fructose corn syrup in food products has been suggested as playing a role in the development of obesity as a public health issue. [11] In a study of literature review, the meta-analysis articles found that consumption of High Fructose Corn Syrup beverages can contribute to childhood obesity. [12]